중복 제거 쿼리문 질문입니다.

mysql> select service_id,version,name from test; 
+------------+---------+------+
| service_id | version | name |
+------------+---------+------+
| 1          | 1       | a    | 
| 1          | 2       | b    | 
| 1          | 3       | b    | 
| 2          | 1       | a    | 
| 2          | 2       | a    | 
+------------+---------+------+
5 rows in set (0.00 sec)
 
mysql> 
mysql> select service_id,version,name from test group by service_id,name;
+------------+---------+------+
| service_id | version | name |
+------------+---------+------+
| 1          | 1       | a    | 
| 1          | 2       | b    | 
| 2          | 1       | a    | 
+------------+---------+------+
3 rows in set (0.00 sec)
 
mysql>